Transdermal delivery is desirable to reduce the side effects associated with the oral administration of a drug such as abdominal pain, nausea and vomiting and also to offer a patient freedom from injections and surgical implantations. Transdermal delivery is provided through a transdermal patch which provides sustained release of a drug for about a week. Transmittal delivery also bypasses the significant metabolism associated with oral administration of the drug.
The present invention is directed to novel duplex prodrugs that provide a significant increase in the transdermal flux of such drugs across human skin, as compared to the basic drug. The prodrug of the present invention may increase the transdermal drug delivery rate either by a solubility improvement or by a permeability improvement, or a combination of both.